Direct connection between the different QCD orders for parton distribution and fragmentation functions

TL;DR

This paper derives universal formulas that directly connect NLO and LO QCD parton distribution and fragmentation functions, simplifying calculations across different types.

Contribution

It provides the first universal formulas linking NLO and LO PDFs and FFs, applicable to all types with only splitting functions differing.

Findings

Formulas are universal across all PDFs and FFs.

Simplifies the transition from LO to NLO calculations.

Enhances the consistency of QCD analyses.

Abstract

The formulas directly connecting parton distribution functions (PDFs) and fragmentation functions (FFs) at the next to leading order (NLO) QCD with the same quantities at the leading order (LO) are derived. These formulas are universal, i.e. have the same form for all kinds of PDFs and FFs, differing only in the respective splitting functions entering there.